Door for floors and sidewalks.



P. 'W. LEONHARD. noon FOB. FLOORS AND. SIDEWALKS.

APPLIOATION FILED JULY"17, 1913. 1 1 1 5 ,554, Patented Nov. 3, 1914.

2 SHEBTSSHEET 1.

. WITNESSES: 0716 7;?

A TTOR/VEYS.

THE NORRIS PETERS CO.. PHOTO-LITHO WASHINGTON, D. C

P. W. LEONHARD. DOOR FOR FLOORS AND SIDEWALKS. APPLICATION FILED JULY17, 1913.

1,1 15,554. Patented Nov. 3, 1914.

2 SHEETSSHEET 2.

WITNESSES; WWW;

ATTORll/EVJ.

THE NORRIS PETERS CO., PHOTO-LITHQ, WASHINGTON. D c

summer; W. LEoNHaRi), or BUFFALO, NEW YORK.

DOOR FOR FLOORS AND SIDEXVALKS.

To allcuiiom it may concern: i Be it known that I, FREDERICK W. LEON--I-IARD, a citizen of the United States, residing at Buffalo, in thecounty of Erie and State of New York, have invented new and usefulImprovements in Doors for Floors and Sidewalks, of which the followingisa specification. This invention relates to a trap door for sidewalks,floors or similar purposes.

The objects of this invention are to provide a door having a walkingsurface of concrete which is not as slippery as and is. more durablethansteel or iron, to provide a concrete slab which is of shallow depth andgreat strength so that the same may be counterbalanced by a minimumweight, to provide means for counterbalancing the door at. all points ofthe vertical are through which it swings so that it may be opened orclosed with a minimum amount of effort,

to provide means forpivotally supporting the door on the underside ofthe walk or floor so as. 'to' keep the pivitalconnectioiis free fromdirt, snow or ice and have them easily, accessible for inspection,

oiling or repairing and carry dead load only, to provide'a door with awalking surface that is absolutely flush with the Walk or floor when thedoor is closed, to provide means whereby the door is waterproofed atside, heel and toe, to provide the door with means whereby the same islocked auto-- matically bothin its closed and in its open positions andmay be released conveniently, and. to so organize the parts that whenthe door is closed no part of it seriously interferes with the underheadroom and when the same is open no part of it interferes with the wellopening so that the same is freely accessible from above and below, to

provide a door which is practically indestructible, to provide a doorhaving glass vault lights in a reinforced concrete slab and to provide adoor which permits the glass vault lights to be placed directly 011 andlocked to the tensile reinforcement of the concrete slab.

In theaccompanying drawings: Figure l is a longitudinal sectionalelevation ofthe door embodying my improvements, the left. v half of thesame being in a closed position and the right half in an open position.

Specif cation of Letters Patent."

Patented Nov. 3, 1914.

Application filed July 17. 1913, Serial No. 279,501. p

Fig. 2 is a vertical section of the door in its fully open position Fig.3-is a plan of the door corresponding to F lvvith the, parts of thesidewall; orfloor removed. Fig.

l is a section showing the rear View of the,

hinge for pivotally connecting the door with,

the floor, the section being taken in line a Fig. f0. Fig. 51s a sideelevation of this hinge and adjacent parts. Fig. 6 is a transversesection, on an enlarged, scale, of the cross shapedbar which connectsthe heel and toe bars of the door, the section being taken ,in line 6+6,Fig. 3. i Fig. 7

, shows a cross section of the spring joint for" one of the guard gatebraces the section being taken in line 77, Fig. 8. Fig. 8 is a top viewof the same. Fig. 9 isa frag- 'mentary plan view, on an enlarged scale,

of adoor slab showing the frame angles and the details of the vaultlights, reinforcement and method of fastening same. [Fig] 10 is averticalsection ofthesa ne. Fig. 11 is a vertical section showing themethod of ty ng the minor to the major reinforcement. i Fig. 1:2 is across section through the sideportion of the door, we'll frame andgutter.

Fig. "13 shows a longitudinal seetionof the door through the toes of theopposing door leaves showing how the trough shaped bar,

of one leafempties into one of the side gutters. Fig. 14 shows afragmentary longitudinal section of the door showing the heel part ofone door leaf, well frame and adjacent gutter.

Similar characters of reference indicate corresponding parts throughoutthe several views. I

In its general construction the door, as shown in the drawings,comprises two door leaves A, two longitudinal counterbalanced supportingbeams or levers B, B vforeach leaf connected at their front ends withtheunderside of said leaf at the side edges of the-same, hinges Gfor-pivotally connecting' the central parts of said beams with theundersides ofthe floor, a counterweight D connected with the rear end ofeach beam, braces E connecting the beams of each doorleaf, automaticguard gates F arranged on the beams, heel gutters G for draining theheels of the door leaves, atoegutter G for drainingthe joint between.the toes of the door leaves, side gutters G for drainiiigthe a sides ofthe door leaves, and locking dogs H and H for holding the door leaves intheir open and closed positions.

It is to be understood that the toe is the transverse edge of the doorleaf farthest from the pivot of the same, the heel is the transverseedge of the door leaf nearest to its pivot and its sides are the lateraledges of the door leaf extending from the heel to the toe. I

4C1 represents the floor or sidewalk over the vault which may beconstructed in any suitable manner and which contains an opening orwell. The edge of this well is preferably bound by a metal frame 6 ofL-shaped form in cross section.

Each of the door leaves comprises two longitudinal side bars 1, 1, atransverse heel bar 9 connecting the rear ends of the side bars, atransverse toe bar connecting the front ends of the side bars, alongitudinal central bar 5 connected at its front and rear ends with thetoe and heel bar, reinforcing wires 9, 1O connecting the bars, bolts 11and 12 for connecting the reinforcing wires with the bars, a slab 13 ofconcrete which is supported on the bars and in which said reinforcementsare embedded, transparent vault lights 1 1- of glass or similarmaterial, and metal sockets or receptacles 15 for said vault lightsmounted on said reinforcement. The frame-bars 1, 2, 4; and 5 may bestandard rolled angles or may be special rolled shapes. The bars 1, 2and l form the four sides of a square or rectangular frame and thevertical legs or flanges of the same provide protection for the edges ofthe concrete slab 13 while the horizontal legs or flanges thereofprovide a seat for the concrete slab 13, also a place for attachment ofthe reinforcement The central bar 5 is cross shaped in cross section andextends longitudinally on the center line of the door and connects theheel and toe bars 2, 4c. The slab 13 is additionally supported by thereinforcement 9 and the latter is attached to the longitudinal bar 5thus dividing the rectangular frame into approximately two squares, eachof which contains a section of the slab.

Each of the side bars 1 is preferably Z shaped in cross section, asshown in 12, and has an upper flange 1 overlapping the upper edge of thewell frame 6, a lower hori- "Zontal flange 1 which forms a seat for theconcrete slab 13 and to which the reinforcement 9 is tied, a verticalweb 1 connecting these two flanges and forming a protection for the edgeof the slab 13 and a depending drip bead l which is formed on theunderside of the lower horizontal flange at its junction with thevertical web. This drip head is adapted to shed all water which findsits way beneath the upper horizontal flange into the longitudinal gutterG arranged on the inner side of the longitudinal upperinside edge ofwell frame.

the transverse gutter G arranged on the adjacent part of the well frame.The upper horizontal flange 2 of the heel bar is also similar to that ofthe side bars and in addition it has a slight extension 2 toward the toeof the door which eliminates the feather edge of the concrete slab 13and also locks the same securely along the heel. The connecting web 2betweenthe flanges 2 2, is oblique instead of vertical and bent at suchan angle that the upper endv forms practically a tight joint with thewell frame 6 when door is closed and gives a considerable clearance forthe lower end and drip bead 2 when the door is closing thus eliminatingthe possibility of the bead fouling the well frame, as shown by dottedline 9. which is a portion of an arc whose radius is the distance fromthe center of the hinge to the The upper sides of the slab and doorframe are flush and the upper edge of the well frame stops short of thetop of the floor so that the door is flush with the floor, as shown inFigs. 12' and 14.

In a double door 2'. e. a door of two leaves A, such as that shown inFigs. 1, 3 and 13, it is necessary to take care of the water coming inalong the toe joint between the two leaves. In this case each of the toecross bars has an upright web a engaging the edge of its companion slab13 and a horizontal flange l at the lower edge of the web which supportsthis slab. At its upper edge the web of one toe cross bar is providedwith a laterally projecting flange 4 which engages with a rabbet 4 inthe upper edge of the toe cross bar of the other leaf, thereby forming ajoint between the same and also causing the leaf with the flange 1 tooperateas a lock for the leaf having the rabbet st At the junction ofthe vertical web and lower horizontal flange of the toe cross bar havingthe flange l is arranged a depending drip bead 4: which directs anywater passing through the toe joint into the trough or gutter G arrangedat the lower edge of the toe bar ofthe other leaf. The opposite ends ofthe toe bar gutter G project'over into the gutters G of the side bars ofthe well frame so that the water from the toe gutter enters the same.The heel gut ters G and the side gutters (l connect with each other atthe corners of the well and any water entering the same is carried awaybyv a drain pipe 38 connecting with the heel gutter, as shown in Figs. 3and 14.

The central bar 5 is cross shaped in cross section and may either berolled in one piece,

stiffness.

as shown in Fig. 6, or built up in any suitslab 13 and a place forattaching thereinforcement. These various bars are riveted or boltedtogether at their various junctions byflat connection plates or gussetsSand when the door is closed they rest on the edges of the gutters thuseliminating the possibility of any live load acting on the hinges C.

The reinforcement for the door slab 13 shown, in Figs. 3, 9, 10 and 11,is composed of steel wire of high tensile strength and is divided intotwo parts z'. e. the major 9 and the minor 10 reinforcements. The majorreinforcement 9 is made by weaving the wires at right angles to eachother. Along two sides of the slab 13 these wires have loops 9 at oneend which engage the head 9 of a specially designed bolt 11 by means ofwhich they are tied to the door frame bars. On the other two sides ofthe concrete slab the opposite ends of the wires 9 are stretched aroundand securely fastened to the adjacent. frame bars by other speciallydesigned bolts 12 by means of which any slack in these wires may betaken out and certain initial stress given to the same. The advantage ofthis tying and stretching is five fold. First, it gives a taut rigidmesh in which each wire is doing its full share of work, thus makingthe'slab 18 capable of standing a load at least 10 to 12 times that of aslab reinforced in the ordinary manner or of a slab. whose reinforcementis tied but not stretched. Second, the reinforcement is so rigid that itpractically takes all the load and whatever beam action there may be,the

steel acts immediately instead of allowing an initial defiectionto takeplace in the slab necessary to stretch the slack out of thereinforcement as is the case in ordinary rein forced concrete work. Thisprevents the concrete from being stretched beyond its elastic limit andcracking of same. Third, it thus becomes, only necessary to make theslab 13. of a minimum thlc'kness to afford a good walking surface andprovide the necessary Fourth, it permits placing the metal cups 15incasing the glass vault lights l i directly onthe tensile reinforcementand locking them thereto. v Fifth, in a reinforced concrete slab ofsmall depthand small span it is hard to develop strengthof reinforcementby "bond to concrete. Tying and stretching eliminates this difliculty.

The minor reinforcement, see Figs. 9, 10 and 11,- consists of steelwiresplaced adjacent to the vault lights 14 ineach alternate rectangularmesh formed by the major reinforcement. They are of such length as willstring diagonally across oneinesh, wrap once around the junction of themajor rein- I forcement and; allow the free end 10 to stick upvertically into the concrete. ,The

object of this reinforcement is to give a local support for the concreteand to anchor the concrete securely to the major reinforce ment.

Thespeoial bolt connections, see Figs. 9

and 10, are two in number, the first being atie bolt and the second awinch bolt. The tiebOll3'lS similar to an ordinary bolt except that thehead9 is elongated in the direction of the major reinforcing-wire whichit enf gages andis provided atiithe outer end of the elongation with adepending hook or lug 9 whichreceives the loop 9 on the wire 9 of themajor reinforcement.

and secure tie and keeps the reinforcement at a certain definitedistance from the bottom of the slab 13. The) winch bolt 12is alsosimilar to an ordinary bolt with a hexagon head except that a verticalgroove '12 is cut in one of its siX sides. This groove is of such depththat the upturned part 12 of the wire 9 which is seated in this grooveprojectsa little beyond the face or side of the bolt head. The object ofthis groove is best shown by the following explanation as to the methodof fastening wire. The

bolt 12 is placed in the punched hole of the.

lower horizontal flange of the respective frame bar withthe head on theupper side and the nut 12 put on but not tightened. The wire of themajor reinforcement is placed between the. underside of the bolt headand the upper side of the lower horizontal flange of the frame bar andon the side of the bolt shank so that the pull of the wire around theshank of the bolt would tend to tighten the same. The wire is thenpulled as tight as possible by hand and given a one eighth turn aroundthe shank and then bent upyinto the groove in the bolt head. The wrenchis now applied with one.

jaw gripping the side of the bolt head which contains the groove. Thisholds the wire sei curely and the bolt is turned until the wire istightened the desired amount and then the .nut is turned tight. Theadvantage ofv this is that it provides for the major reinforcemerit aquick and secure attachment, taking out all slack and giving a certaininitialf stress. As the shank of the boltturns with I the wireit thusprevents any local orconcentrated stretch of the wire and possible injury therefrom.

The slab provides a wearing or walking surface and may be of cement orbituminous concrete or other suitable material. The,

concrete locks the metal receptacleslforthe vault lights laterally inplace.

The glass vault lights 14 are circular in plan and threaded on thecircumference, as shown at 1 1, so as to screw into the'metalreceptacle.

The advan{ tage of thisbolt is that it provides a quick They are flat onthe top and spherical on the bottom except a small flat shoulder 14around thebottom edge which forms a seat for the gasket 16. The extremeedge 14 of this shoulder is slightly acute so as to grip the gasket.

The exterior of the metal receptaclesis circular in plan at the uppersurface and has an upper octagonal form 14 in the plane of thereinforcement and a lower octagonal form le at the lower surface. Thesetwo octagons are not of the same size in plan and are not equilateralbut are formed of four alternate, long and short sides. The four longsides of the lower octagon 1& produced would form a square slightly lessin size than the square mesh formed by the wires of the majorreinforcement. The two octagons are separated by a circular groove,channel or canal 15 which receives the major reinforcement and thiscanal forms an inscribed circle in the square formed by the long sidesof the lower octagon. The advantage of this construction is that byplacing the long sides of the lower octagon parallel with the wires ofthe maj or reinforcement the cup 15 drops through the mesh until thelower side of the upper octagon bears on the major reinforcement. Thecup is then turned horizontally 45 degrees until the wire reinforcementlies in the circularcanal. This forms the vertical lock for the cup Orreceptacle and the surrounding concrete forms the horizontal lock. Theinside of the cup is circular in plan and threaded to receive the threadof the glass vault lights. A clearance is provided between the inside ofthe cup and the vault light which is filled with suitable cement 15 toprovide for expansion. Around the inside lower edge of the cup there isa shoul der 15 the edge of which is slightly acute so as to grip the gasret. The vault lights rest on the gasket which forms a tight oint andthe gasket is held in place by a metal collar 15 which in turn isfastened to the underside of the metal cup by tap screws 15 as shown inFig. 10.

Each of the beams B is of irregular shape and is composed of a load arm18, a weight arm 19, a connection piece 20 between the two arms and ahinge plate 21. The weight arm supports the counterweight D and iscomposed of a channel or other suitable shape. It lies in a. horizontalposition when the door is closed and is inclined when the door is open.At its outer end it has a means for the attachment of the counterweightD and at the inner end its back is riveted to the inside of the adjacenthinge plate2l. At one end its back'is riveted to the outside of thehinge plate 21 in a downward oblique direction and at such an angle thatit becomes horizontal when the door is open. The load arm 18 is composedof an angle or other suitable shape and it supports the door leaf at itsouter end. The

inner end of the load arm is bent at its junction with the connectingpiece 20 and is riveted to the back of the lower end of this connectionpiece 20, this riveting being further strengthened by a clip angle 22which is also riveted to the back of the connection piece 20 and to thehorizontal leg of the load arm angle 18. The load arm 18 has a secondbend near its outer end where it joins the side bars of the door leafwhich point is approximately one half the distance between the heel andtoe bars. That portion of the load arm 18 between said outer bend andits outer end is horizontal and parallel to the weight arm when the dooris closed.-

This horizontal leg forms the support for the door slab and it isriveted or bolted to the horizontal leg of the side bars of the frame.The arm 18 is straight between the two bends mentioned above and to thisstraight part are riveted two clip angles 28 for supporting theautomatic guard gates. This arm affords a place for connecting the braceangles E. It also forms a support for the brace 25 which gives anauxiliary support to the side bars 1, 1, of the door leaf at a pointapproximately one half the distance between the heel and the point wherethe load arm joins the side bars. The load arm besides aifording a meansof support for the door and automatic guard gates also acts as atransverse guide to bring the door to its proper seat.

The hinge gate 21 is riveted between the backs of the weightarm channel'19 and the connection piece channel 20. It extends above the horizontalflange of the weight arm through which extension is bored a hole toreceive the hinge pintle. Through the edge of the hinge plate from therear is bored a hole 26 to the pin bearing to receive a set screw 27 bywhich means the pin is set to the hinge plate, thus making the pinrevolve in the jaws of the hinge. The hinges C are of the ordinary typewith two vertical jaws bored to receive the pin and holes in thehorizontal flanges to receive the stay bolts. The hinges take dead loadonly.

The counterweights may be of concrete or other suitable material hung ona rod or hook which engages a hole in the outer end of the weight arm.As the center of gravity of the automatic guard gates is practically thesame distance from the hinge C whether thedoor is closed or open and asit is desirable to have the'nioment of the load arm slightly greaterthan the moment of the counterweight arm in order to overcome anypossible tendency of the door kicking up should the locking devicebecome defective and yet have a door that is practicallybalanced at allpoints of the vertical are through which it swings, the position of thecounterweight to take care of these conditions is arrived at as follows:

Assuming that the weight of the load arm .18 and the bracing E balancesthe weight of the weight arm 19 and further assuming that the centerofgravity of the door leaf and guard gates F is at a point half waybetween the heel and toe and on the underside of the leaf then by fixingthe length I and guard gates, as at X at the left side of of a lVarrentruss.

Fig. 1. By placing the counterweight slightly inwardly from X towardhinge C as at Y the condition of load moment, being greater than weightmoment is fulfilled and placing the weight slightly above Y as at Z itgives the same effect as at Y when door is in the closed position but Zgives a slight increment tothe weight moment as the door opens thustaking care of the constant movement exerted by the guard gates F. By

figuring the weights and center of gravity of the various parts theexact position may be calculated. I

Thebracing E comprises a channel 28 which runs between the twoconnection pieces 20 and is riveted to the top flanges of same by meansof gussets, two angles 24 which run from gussets at the outer end of theload arms 18 to a gusset riveted to the lower flange of the bracechannel 28 at.

its center of span.

The automatic guard gates F are hinged to the horizontal legs of theclip angles 23 on the load arm and swing through the same vertical arcwith the door. They are composed of flat iron bars riveted in the shapeThe top and bottom cords 30, 31 of the gates on the lock leaf having thelocking flange 49 are of such length that these gates swing within acircle whose'radius is slightly less than the distance'from the hingepin of this leaf to the toe ofthe opposite trough leaf having the troughG so as to give a slight clearance therebetween. The gates of the troughleaf are of such length so as toswing and give a slight clearance on thegates of the lock.

leaf. This permits the lock leaf to be fully opened by disconnecting achain 7 between the two opposite gates without disturbing the troughlead. It also permits the two door leaves to be closed at the same timewithout interference from the gates. v

At the junction of the top cord 30 and the outer web member 32 of eachgate the connection with the chains f is made by means of a tie boltsimilar to that used for tying the reinforcement. To the nose of thistie bolt the chain f is attached which thus gives a flexible connectionbetween the gates of the opposite leaves both when the door is closed oropen or any intermediate position. Each of these gates is held laterally'bv an iron brace preferably composed of two bar. sections 33, 38*having their extremities hinged to' the top cord 30 and to the clipangles 28 riveted to the underside of the central bar 5 of therespective door leaf. The opposing ends of thebrace sections areconnected by a flexible spring joint so that the gate may be. foldedflat'on the leaf when the door is open after disconnectmg chain 7 thusgiving access to the well. opening. This spring. oint preferably c'om-'prises a pivot pin or rivet 3a connecting the opposing ends of the bracesectlons 88, 33

and a spring finger 34 -being an extension. of the brace section 33toward the brace sec-" tion 83 and provided with an abrupt stop 34 and arivet head or wedge projection-34 adaptedto engagelwith opposite sidesof the brace section 38 while this'brace is straightened. members areturned in a direction for nioving the stop 34? away from the section 33*and carrying the wedge projection 34 underneath the'same. The advantage.of this is that in breaking the joint the upper bar passes over thelower bar and rivet head 3% which tends to spring that portion of thelower bar forming the finger; thus oflering the necessary resistance tokeep the joint rigid for all axial forces but the joint may be easilybroken by a lateral force intelligently applied by the hand on the sameside of the brace member on which the rivet head 341 is arranged. Inother words the joint is held rigid on one side frornaxial forces by acouple of which the rivet connection is one force and the comparativelyflat projection 34 in conjunction with the spring resistance of thefinger portion of the lower bar forms the second force. If before thedoor is closed it is neglected to unfold the gates F they'will fall bygravity into that position when the door is closed and thus be ready toprotect the well when tends to increase this eccentricity thus hold 7ing the joint rigid. I

a By extending the horizontal leg of the clip angles 23 which attach thetop and bottom cords 30, 31 of the gates to the load arms, so that theirhinges are beyond the vertical leg of the load arm angle the gates Fwhen door is open may be swung outward over the sidewalk as well asinward over the well by simply detaching either end of the gate braces.

For folding this brace its If desired only one door leaf andassociatedparts need be employed in the case of a well of comparatively smallarea.

Locking means are provided for holding the door leaves in both closedand open positions, these means preferably comprising the two pairs oflocking dogs H, H The first set of dogs H lock the door in the openposition and the second H lock the same in its closed position. Themembers of the first set of locking dogs are situated on the outside ofthe counterbalanced beam and are fastened to the underside of the walkor floor and automatically engage a lug angle 71, riveted on the outsideof the connection piece 20 and can be released from above by a rope 72.The members H of the second set of lockingdogs are situated on theinside of the counterbalanced beam and are also f sten'ed to theunderside of the walk or floor so as to engage the upper flange of theweight arm, as shown in Fig. 1. The last mentioned dogs may also bereleased by a rope conveniently placed similar to that used inconnection with the dogs H or by any other suitable means.

I claim as my invention:

1. The combination of a floor having a well, a door adapted to closesaid well, a

two armed lever ivoted to swim verticall on the underside of said flooradjacent to one edge of the well and having its front arm connected withthe underside of said door between the heel and toe thereof said leverhaving its front arm deflected downwardly adjacent to the fulcrumthereoi while its rear arm is arranged underneath said floor, and acounterweight mounted on the rear arm of said lever.

2. The combination of a floor having a well, a door adapted to closesaid well, a two armed lever pivoted to swing vertically on theunderside of said floor adjacent to one edge of the well and having itsfront arm connected with the underside of said door between the heel andtoe thereof said lever having its front arm deflected downwardlyadjacent to the fulcrum thereof while its rear arm is arrangedunderneath said floor, a counterweight mounted on the rear arm of saidlever, and means for looking said lever in an open and in a closedposition.

3. The combination of a floor having a well a door adapted .to closesaid Well, a beam orv lever pivoted on said floor and carrying saiddoor, and means for locking said door in its closed and in its openpositions comprising dogs pivote on the underside of said floor andadapted to engage with said beam or lever on opposite sides of its axis.

4. The combination of a floor having a well, a door adapted to closesaid well, a beam or lever pivoted on said floor and carrying said door,and means for locking said door in its closed and in its open positionscomprising dogs pivoted on the underside of said floor and adapted toengage with said beam or lever on opposite sides of its axis andreleasing lines connecting with said dogs.

5. The combination of a floor having a well, a door adapted to closesaid well, two levers pivoted to swing vertically on the underside ofthe floor adjacent to opposite corners of the Welland each having afront arm which is connected with the underside of said door between theheel and toe thereof and is deflected downwardly adjacent to its fulcrumto form an elbow and also having a rear arm arranged underneath thefloor, a counterweight connected with the rear arms of said levers, anda transverse beam connecting the elbows of both levers.

6. The combination of a floor having a well, a door adapted to closesaid well, two levers pivoted to swing vertically on the underside ofthe floor adjacent to opposite corners of the well and each having afront arm which is connected with the underside of said door between theheel and toe thereof and is deflected downwardly adjacent to its fulcrumto form an elbow and also having a rear arm arranged underneath thefloor, a counter weight connected with the rear arms of said levers, atransverse beam connecting the elbows of both levers and oblique bracesconnecting the central part of said beam with the front parts of thefront arms of both of said levers.

/Vitness my hand this 16th day of July, 1913.

FREDERICK W. LEONHARD.

Witnesses:

HARRY L. LEONHARD, THEO. L. Porr.

Copies of this patent mav be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, I). G.

